Device for adjusting the reticle of an aiming telescope

Abstract: An aiming telescope has an inner tube mounted within the main tube on the eyepiece side, e.g. with a ball-and-socket joint, for receiving the inversion system and the reticle. For adjusting the reticle a pair of adjusting spindles disposed at right angles to each other are provided, the restoring forces being applied by a spring which is supported on the ball of the ball-and-socket joint at a distance from the center of the ball, on the one hand, and on the main tube, on the other hand.

Description: The present invention relates to an aiming telescope having a main tube with eyepiece and objective in which an inner tube is mounted with a joint on the eyepiece side for receiving an inversion system and a reticle, a pair of adjusting spindles disposed on the main tube at an angle to each other and acting on the inner tube at a distance from the joint, and at least one spring for urging the inner tube against the adjusting spindles. Such aiming telescopes are known. They permit the reticle to be moved relative to the weapon so that it can be brought into agreement with the meeting point. Since reticle and inversion system are shifted jointly relative to the target imaged by the objective the reticle remains in the center of the visual field, regardless of the necessary adjusting motion (centered reticle). The adjusting motion is started by the pair of adjusting spindles disposed at right angles to each other. To produce the necessary restoring force one normally uses one or two springs disposed between the main tube and the inner tube at a distance from the joint, i.e. acting perpendicular to the inner tube axis. The springs disposed between the inner tube and the main tube restrict the adjusting distance so that the adjusting distance may be too short if the aiming telescope is not properly mounted on the weapon. For reasons of space the spring size is also small compared to the relatively large adjusting distances, resulting in great variations in spring force over the adjusting distance. Furthermore, a relative motion occurs between spring and main tube or inner tube, leading to frictional losses and at the same time to a danger of the optical system being soiled by abrasion. In addition, the inner tube can only be assembled with a prestressed spring, which increases the assembly effort. US-A-2,580,280 discloses an aiming telescope having a joint formed by a space bar which has a tongue which is received in a slot of a flange on the objective side of an inner tube housing the reticle. The inner tube is urged towards the space bar by a coiled spring coaxially arranged in a section of the main tube having an enlarged diameter to react between the flange of the inner tube and a ring at the objective. The inversion system is fixed to the main tube between the inner tube and the eyepiece, so that the reticle is not centered. The invention is therefore based on the problem of providing an aiming telescope with a centered reticle, which telescope is easily assembled and has a large adjusting distance and eliminates the danger of the optical system being soiled by abrasion. This is obtained according to the invention by an aiming telescope in accordance with claim 1. Supporting the spring or springs at a distance from the center of the ball of the ball-and-socket joint obtains the necessary torque about the center of the joint. The force of the spring or springs is preferably aligned parallel to the inner tube axis. This utilizes the spring force completely, i.e. obtains the highest torque. The spring or springs can be formed as compression or tension springs. In case of more than one spring one can use both compression springs and tension springs. Further advantageous embodiments of the invention are found in the subclaims. With the inventive aiming telescope there is relatively a lot of room in the area of the reticle and the optics of the inversion system. This results in a large adjusting distance. This room can also be utilized to give the optical components, e.g. the field lens or reticle, a larger design and thus improve the optical performance. To obtain high precision and firing stability the joint must be mounted free from play, which requires considerable time with the conventional aiming telescope. By contrast, in the inventive aiming telescope the clearance of motion of the joint is eliminated by the springs acting on the joint portion fixed on the inner tube. This substantially reduces the time required for adjusting play during assembly and at the same time considerably improves the resistance of the inversion system to shock stress during firing. Since the springs are only installed after the inner tube with the inversion system is inserted into the main tube the assembly of the inversion system is not impeded by prestressed springs. At the same time one can use amply dimensioned coil springs according to the invention which have a functionally favorable characteristic. Since no relative motions occur between the spring and the inversion system or the main tube no abrasion arises in the inventive telescope which could lead to the optical system being soiled. In the following an embodiment of the inventive aiming telescope will be explained in more detail with reference to the schematic drawing, in which: Fig. 1 shows a longitudinal section through part of the aiming telescope; Fig. 2 shows a section along line Il-Il in Fig. 1. The aiming telescope has main tube 1 within which eyepiece 2 is seated at one end and the objective at the other, front end not shown. Mounted within main tube 1 is inner tube 3 with ball-and-socket joint 4 which is disposed at the back end of inner tube 3 on the eyepiece side. Inner tube 3 contains inversion system 5 formed by two lenses and in front of it reticle 6 formed e.g. as cross-lines. At the front end of inner tube 3 is field lens 7. For adjusting reticle 6, i.e. bringing it into agreement with the meeting point, inner tube 3 is swiveled about ball-and-socket joint 4 with respect to main tube 1 fastened to the weapon. For this purpose a pair of adjusting spindles 8 extend perpendicular to each other through main tube 1 at a distance from ball-and-socket joint 4, each provided with turning knob 9. The other end of adjusting spindle 8 acts on spherical bump 10 on inner tube 3. Spherical bump 10 ensures a point contact of adjusting spindle 8 on inner tube 3 in every angular position of longitudinal axis 11 of the inner tube relative to the longitudinal axis of main tube 1. The restoring forces are applied by coil spring 12 which loads inner tube 3 against adjusting spindles 8. Coil spring 12 engages at one end recess 13 facing eyepiece 2 on ball 14 of ball-and-socket joint 4 forming the joint portion fixed on the inner tube. Recess 13 has end wall 15 extending radially to the center of the joint, i.e. to the center of the ball, and perpendicular to longitudinal axis 11 of the inner tube. End wall 15 supports one end of coil spring 12, i.e. at a distance from the center of ball 14 and thus from longitudinal axis 11 of the inner tube which is greater than the outside diameter of the inner tube. The other end of spring 12 acts on annular projection 16 mounted on main tube 1 on the side of ball 14 facing eyepiece 2. Projection 16 can be formed by a threaded or snap ring which engages a corresponding thread or groove on the inner wall of main tube 1. Axis 17 of coil spring 12, i.e. its force, extends substantially parallel to inner tube axis 11. Fig. 1 shows only one spring 12. However one normally provides several, e.g. three, circumferentially distributed springs 12 between end wall 15 and annular projection 16. For assembly the inner tube provided with inversion system 5, reticle 6 and field lens 7 is inserted into main tube 1 from the eyepiece side until ball 14 of ball-and-socket joint 4 hits socket 18 which extends toward the front from end wall 15 of ball 14. Springs 12 are then introduced and inner tube 3 and springs 12 fixed with the ring with projection 16.

Claims: An aiming telescope having a main tube (1) with eyepiece (2) and objective in which an inner tube (3) is mounted with a ball- and- socket joint (4) on the eyepiece side for receiving an inversion system (5) and a reticle (6), a pair of adjusting spindles (8) disposed on the main tube (1) at an angle to each other and acting on the inner tube (3) at a distance from the joint (4), and at least one spring (12) for loading the inner tube (3) against the adjusting spindles (8), characterized in that the spring (12) for loading the inner tube against the adjusting spindles is supported on the ball (12) of the ball- and- socket joint (4) at a distance from the center of the ball (14), on the one hand, and on the main tube, on the other hand. The aiming telescope of claim 1, characterized in that the force of the spring (12) is aligned parallel to the inner tube axis (11). The aiming telescope of claim 1 or 2, characterized in that the spring (12) is supported at one end on an end wall (15) of the ball (14) of the ball-and-socket joint (4), said end wall extending radially from the center of the ball (14) and perpendicular to the inner tube axis (11). The aiming telescope of any of the above claims, characterized in that the spring (12) is disposed on the side of the ball (14) of the ball-and-socket joint (4) facing the eyepiece (2). The aiming telescope of claim 4, characterized in that the spring (12) is supported at its other end on a projection (16) fastened to the main tube (1).

Inventors: MURG ERWIN, MURG, ERWIN
Applicants: SWAROVSKI OPTIK KG
Application year: 1994
Main classification: F41G1
IPC codes: F41G1